code: def test_append(self):
      content1 = """
              {
                  "a": 5,
                  "b": "text"
              }
              {
                  "a": 13
              }"""
  
      content2 = """
              {
                  "q": 555,
                  "r": "something"
              }
              {
                  "a": {
                      "b": [1, 2, 3]
                  }
              }
              {}"""
  
      with create_file(content1) as filename, open(filename, "a") as fp:
          splitter = JsonFileSplitter(filename)
          self.assertEqual(splitter.get(), {"a": 5, "b": "text"})
          self.assertEqual(splitter.get(), {"a": 13})
          self.assertEqual(splitter.get(), None)
          fp.write(content2)
          fp.flush()
          self.assertEqual(splitter.get(), {"q": 555, "r": "something"})
          self.assertEqual(splitter.get(), {"a": {"b": [1, 2, 3]}})
          self.assertEqual(splitter.get(), {})
          self.assertEqual(splitter.get(), None)
          splitter.close()
  
file_path: neptune-client/tests/unit/neptune/new/internal/utils/test_json_file_splitter.py
imports: import unittest
  from neptune.internal.utils.json_file_splitter import JsonFileSplitter
  from tests.unit.neptune.new.utils.file_helpers import create_file
label_desc: Use image node_id 2 for calling the TestJsonFileSplitter obj's underlying member method code with example usage: obj.test_append() without return types